What aspects of a website are affected by accessibility?

Even if you're not required to be accessible online and a private organization, there's been a surge of law firms taking on the opportunity to file suit or settle for damages based on a site not being accessible to visitors. It's important to keep your site up to at least ADA WCAG 2.0 AA standards to avoid lawsuits.

These are the aspects of a website are affected by accessibility:

Design - Colors, font sizes, styles, and layouts
UX / UI - Capable of being used by alternative browsers, and screen readers like JAWS https://www.freedomscientific.com/Products/Blindness/JAWS
Development - HTML and pages capable of navigation by people using the keyboard only, assistive devices, and screen readers
Media - Videos with captions, players capable of being turned on or off with devices, and slideshows / features with play / pause actions. PDF and documents that also meet accessibility standards